Method for making sheet or web material



June 1, 1954 w. c. HUEBNER METHOD FOR MAKING SHEET OR WEB MATERIAL 3sheets-sheet 2 Filed April 4, 1951 vJune 1, 1954 W. c. HUEBNER METHODEoR Filed April 4, 1951 MAKING SHEET 0Rl WEB MATERIAL 3 Sheets-Sheet `3IN1/EN TOR. Wf//mm C. #us/ver Patented June 1, 1954 UNITED STATES PATENTOFFICE METHOD FOR MAKING SHEET R WEB MATERIAL William C. Huebner,Mamaroneck, N. Y., assignor to The Huebner Company, Dayton, Ohio, acorporation of Ohio 1 claim. 1

This invention relates to improvements in a method of making sheets orwebs.

The. invention contemplates producing sheets or webs similar to paper,cloth, linen, felt, asbestos, or other iibrous-like sheets or webs fromdeposits of compositions in liquid, semi-liquid or mobile liquidparticle form and containing electrically chargeable and ionizablefibrous-like materials and. which compositions are then conditioned,dried. or set.

The invention also contemplates making sheets or webs from cellulosenitrate, cellulose acetate, resi-ns, synthetic resins or other suitableplastic compositions in liquid, semi-liquid or mobile liquid particleform and containing electrically chargeable and ionizable material bydeposits of the compositions and which deposits are then conditioned,dried or set.

Thezinvention further contemplates producing sheets or webs from anyother composition containing electrically chargeable and ionizablematerial and which composition can be deposited in liquid, semi-liquidor mobile liquid particle fornfr and then conditioned, dried or set.

- lllhfe invention further contemplates producing. sheets or webs fromcompositions containing "magnetically responsive material, such as`metal particles or powder,v and which compositions can be deposited inliquid, semi-liquid or mobile liquidl particle form and thenconditioned, o

dried or set. a

The: term web as used herein designates a ribbon of thev material ofsubstantial length and whichl can be Wound. upon a drum while the termsheet as used herein designates a ribbon of the material which is ofrelatively short length and wherein the separate sheets must bev stackedas distinguished from being continuously wound on a drum.

This application is a continuation-in-part of my application Serial No.40,374, filed July 23, 1948, and. now abandoned, which was a division ofmy copending application Serial No. 649,315, iiled February 21, 1946,now Patent No. 2,615,822,

issued October 28, 1952, which, in turn,` is a continuation-in-part ofmy application Serial No, 533,500, led May 1., 1944, now abandoned.

n The method contemplated by the. invention employs a. principle. whichis altogether novel and therefore there is no adequate term now in usecovering this principle. Consequently I have originated a new term forthe principle employed uid, semi-liquid or mobile liquid particle formand containing magnetically responsive materials or materials renderedmagnetically responsive by being electrically charged and ionized toelectromagnetic force to cause the migration of the compositions from aretaining element to a receiving Surface by the lines oi' force oi themagnetic ield or fields of said electromagnetic force and undersubstantially atmospheric conditions.

An object of the invention is to provide an improved method for makingsheets or webs of the character referred to, rapidly, economically andwith controlled uniformity of thickness and texture in accordance withdesired characteristics.

Another object is to provide an improved method for making sheets orwebs of the character specied and wherein the sheets or webs can beproduced in one continuous operation so as to consist of a singledeposited layer or of a plurality of laminated deposited layers of thesame composition or of diierent compositions with the layers being ofthe same or diiierent thicknesses as desired.

Another object is to provide a method for making sheets vor webs andwhich method can be` used with equal facility for making fibrous-likesheets or webs or for making film-like sheets or webs or for producingcoatings on previously formed sheets or webs.

Another object is to provide a method for making sheets or webs andwherein the sheets or webs simultaneously with their production may bereenforced by a reenforcing element integrated therewith or embeddedtherein.

Another object is to provide an improved method of forming upon areceiving or reenforcing base materialy or element a layer or coating ofpredetermined thickness of a composition containing magnetic responsiveor electrically chargeable and ionizable material and which compositionis transferred to and deposited upon the base material or element whilein liquid, semi-liquid or mobile liquid particle form by the lines offorce of an electromagnetic field of force and thereafter isconditioned, dried or set.

Another object of the invention is to provide a method of making sheetsor webs from compositions in liquid, semi-liquid or mobile liquidparticle form and containing magnetically responsive or electricallychargeable and ionizabl'e material and wherein the composition istransferred from a supply source and is deposited on aesdove 3 a movablesupport by the lines of force of an electromagnetic field or iields or"force and created at a predetermined location or locations relative tosaid movable support.

Further and additional objects and advantages not hereinbefore specifiedwill become apparent during the detailed description of the method andof an apparatus for carrying out the method and which apparatus isillustrated in the accompanying drawings, wherein Fig. l discloses,partially in front elevation and partially in section, an apparatuscapable of performing the method of the invention and which apparatus,in this instance, is shown as co1nprising three composition depositstations of such character that the composition can be deposited at onlyone of the stations or at a plurality7 of the stations as desired,depending upon the character of the sheet or web to be produced, i. e.,if it is to be of a single thickness of composition or of a plurality oflayers of the same composition or diierent compositions.

Fig. 2 is a sectional view taken substantially on line 2 2 of Fig. 1looking in the direction of the arrows. Fig. 3 is a view on an enlargedscale of a portion of Fig. 1, i. e., the left hand deposit station ofFig. l, but shows a different form of movable support from which thecomposition is deposited' than does Fig. 1.

Fig. 4 is a fragmentary enlarged view of the belt or movable support ofFig. 3 showinD` a deposit thereon of a composition containing fibrousmaterial, such as paper or the like, and disclosing the manner in whichthe suction drums operate to remove moisture from the composition andbelt.

Fig. 5 is a view similar to Fig. l but illustrates a reenforcing elementintegrated with the deposited composition, in this instance said elementbeing embedded in the composition.

Fig. 6 is a fragmentary sectional view taken substantially on line 5 6of Fig. 3 locking in the direction of the arrows, and

Figs. '7 and 8 are diagrammatic illustrations, respectively, of themanner in which the composition is deposited on the movable support whenthe composition retaining element is stationary and when said element isoscillated transversely 0f the support within the electromagnetic eld.

The apparatus disclosed in the drawings and capable of carrying out themethod comprises a base I8, which is provided adjacent its right handend and along its longitudinal edges with upstanding side Walls Il. Theupper edges of the side walls Il support spaced upwardly extendingstandards I2, there being in the present illustration three pairs ofsaid standards since, for purposes of illustration, the apparatus Willbe described as having three `composition transfer and deposit stations.However, it will be understood that a dierent number of such stationsmay be provided as desired.

Each pair of standards l2 supports between its upper end a main orreservoir tank I3 which holds the liquid, semi-liquid or mobile liquidparticle composition containing magnetic responsive material or materialwhich becomes magnetically responsive when electrically charged andionized and which composition is to be transferred and deposited andformed into a sheet, web, layer or coating. Each tank I3 is provided onits underside with a valved outlet I4 to which is connected one end of aflexible hose` i5. Each standard I2 intermediate its top and lower endsis pro- 4 vided with a bayonet slot i 6 to receive and mount thereintrunnions I'I formed on the opposite ends of a removable intermediateand smaller supply tank iS, see Fig. 2.

The lower end of each flexible hose I5 is connected to the inlet of asupply tank I8, wherefore a regulated amount of the composition can flowfrom the reservoir I3 through the valved outlet i4 thereof, through thehose I5 and into the supply tank I8. The supply tank i8 on its undersideis provided with a series of longitudinally spaced vertically extendingnozzles I9 While each tank i3 is at its inlet connected to a separateconduit 2D that extends to a regulated source of supply of pressurehuid, Wherefore regulated pressure can be created in each tank I8 tocause a greater or lesser now of the composition through the nozzles i9.It will be understood that the pressures in the various tanks I8 may beindependently and separately regulated so as to provide for a greaternow from one of 'the tanks than from the other. In addition, thecomposition in one of the tanks may be of a different liquid consistencyfrom the composition in an. other tank and hence different pressureswould be required to produce the desired outward flows of the twodiiereni-l compositions. A pressure gauge ZI is provided for each supplytank I8 so the operator can determine when the desired pressures havebeen created for each of the supply tanks.

Each pair of standards i2 supports an inclined plate 22 which extendsbeneath the row of outlet nozzles i9 and cach plate 22 may be providedwith suitable means for heating the same as, for instance, an electricheater 23. It will be under@ stood that in some instances thecomposition Will be of such character that it is desirable to heat thesame as it flows along the inclined plate 22, either to maintain thecomposition in the proper liquid consistency or to facilitate the flowthereof onto a composition retaining element later to be referred to.

As previously stated, the apparatus embodying.

the invention eiects the transfer of thecomposition to and the depositthereof on a movable support by means of the lines of force of anelectromagnetic field of force. In the present machine there are threeunits disclosed for creating three separate electromagnetic forces andeach of these units is identical with the others and hence only one needbe described in detail.

The standards of each pair of standards I2 are provided on theiradjacent faces with bossed openings in which a supporting rod 2li ismounted for limited endwise movement, said rod being held againstrotation in the openings by pins 25, see Fig. 6, carried by the rod andlocated in slots formed in one of the bosses. The rod 24 mounts aclamping member 2S and which in turn is secured to and supports avertically extending composition retaining element 29 extendinglongitudinally of the rod and provided at its lower end with alongitudinal series of comb-like: ne

.pointed teeth 3B. The composition retaining'element 29 is spacedslightly from the lower longitudinal edge of the plate 22, whereforecomposition on the plate 22 can flow down saidlplate and onto theretaining element and thence' to the comb-like teeth 313 thereof whereonit will be held or retained by capillary action. l

A second supporting rod 33 is rigidly supported by the walls I l andmounts throughout its longitudinal length a series of electromagnets 35provided With eld barsSE shapedto provide ,sharp edges that are slightlyspaced apart with the center of the spacing verticallyl in line with thepoints of the teeth 39 of the retaining element 29. The magnets areconnected to a suitable source of electrical energy as` will later beexplained and when energized will create a inagnetic field of forcebetween the iield bars 3% and including the space between said iieldbars and thel points of the teeth 3i) of the retaining element 29. Aswill later be explained, the lines of force of the electromagnetic eldor fields of force act to cause the migration of the composition fromthe teeth 30 of the retaining element 29 through the space and onto amovable supporting member later to be referred to.

The supporting rod 33 and magnets 35 are mounted within a supportingcylinder 3'.' rotatably supported in and preferably insulated from theside walls il, with the field bars se of the magnets closely adjacent tothe inner circumference of the cylinder. inasmuch as there are threeunits in the apparatus disclosed, three such cylinders 3! areillustrated and such cylinders contact the underside of and support themovable member upon which the composition is deposited to maintain thedesired spacing between the member and the retaining element 29, suchmember being illustrated as an endless belt. The retaining element 29and the series of electromagnets are of such longitudinal length thatthey extend substantially the full transverse width of the endless beltor other movable support.

The side walls Il adjacent their left hand ends as viewed in Fig. lrotatably support a driving roller 38 and an idler roller 39 arrangedparallel to each other with the roller 3&3 spaced vertically above theroller 38. The walls l i adjacent their right hand ends rotatablysupport idler rollers 40 and 4I which also are arranged in verticallyspaced parallelism and are mounted for adjustment in a horizontal plane.The rollers 38, 39, 49 and 4I are adapted to mount various forms ofendless belts later to be referred to and which constitute the movablesupport for the deposited composition, it being understood that theadjustment of the rollers 40 and il in the horizontal plane provides theproper tautness to the endless belt.

The roller 38 is driven by a variable speed motor unit 42, see Fig. 2,which may have a geared reduction embodied therein, while the shaft onwhich said roller 38 is mounted is operatively connected by suitabledrive trains indicated at 43, and each train includes a clutch and arotatable cam drum d4, see Figs. 2 and 6, having a cam groove in whichtravels a follower carried by a reduced portion d6 of the rod 24.

It will be understood that the shaft of the roller 38 is thusoperatively connected with each of the rods 24, and hence when saidshaft is rotating and the clutch of each train is engaged each rod 24will be given a predetermined limited endwise oscillating movement witha resultant oscillating movement of the retaining element 29. Thepurpose of this arrangement will be ex plained later.

v As previously stated, the composition is deposited on the movablesupport which is in the form of an endless belt, the deposit being madeeither directly on the support or upon a re ceiving or reenforcing baseelement or member traveling over or upon said support.

L In Fig.A 1 the endless belt vis shownas a thin smooth or polishedsteel or metal belt 4'! eX-' 6. tending around the rollers 38, 39, 49and V4l and driven by the roller 38. This formof belt willi be employedin the apparatus when producing by the method sheets or webs offelt-like composiA tion.

When sheets or webs from liquid, semi-liquid er mobile liquid particlecompositions containing electrically chargeable and ionizable iibrous orpulp materials by the method a foraminous endless belt is used in placeof the steel belt 4l and' such foraminous belt is indicated at 49 inFigs. 3, 4 and 5 and consists of a layer of felt or other suitable andsimilar material interposed between fine screened mesh. It will beunderstood that the purpose of using such a belt is to allow themoisture to be withdrawn from the compositionpreviously deposited on thebelt byv the elec-- tromagnetic eld of force between the eld barsl ofthe electromagnets so that the fibers of rthev composition will befelted together when the composition is dried.

The compositions which may be employed inl the apparatus and in thepractice of the method are in liquid, semi-liquid or mobile liquidparticle form and contain magnetically responsive material or materialwhich becomes magnetically re sponsive when electrically charged andionized in such a proportion that the ionization of said material underelectrical influence renders the composition mobile and susceptible tomigration from the retaining element 29 to the belt underl the influenceof the magnetic lines of force of the electromagnetic ield of force andunder substantially normal atmospheric conditions. It isY known thatwhen certain materials are electrically charged they are ionized andwhen mobile become susceptible to the action of a magneticiield of forceand advantage is taken of this phenomenon in the practice of the methodembodying the invention. As illustrative of such a composition referenceisy made to a liquid, semiliquid or mobile liquid particle compositioncontaining electrically chargeable and ionizable fibers and wherein theproportion of bers present in the composition is from 60 to '70% whilethe liquid content of the composition would range from 30 to 40%.

It will be noted that the illustrated composition referred to differssubstantially from ordinary paper pulp as used in the conventionalmanufacture of paper since such paper pulp contains only ten or lesspercent of brous material and ninety or a greater percent of liquid. Thelow liquid content of the compositions which it is contemplated using inthe apparatus by which the method of the present invention is carriedout provides the decided advantage that the deposition of thecomposition can be quickly dried, conditioned or set, particularly ascompared to deposits of ordinary paper pulp.

It is proposed to employ two series of rotatable tubes 9 which aresupported by the side walls I l and extend transversely of the endlessbelt with the tubes of one series located intermediate the cylinders 3land contacting the upper side of thel upper reach of the belt, while thetubes of the other series are positioned to contact the upper side ofthe lower reach of the belt. Each tube 49 is provided with a pluralityof circularly spaced series of longitudinally spaced radially extendingports 59 which are adapted to register as the tubes rotate withlongitudinally spaced passages 5l formed in a stationary elongatednozzle 52 that extends longitudinally within the tube as clearly shownin the drawings. Y

The passages 5| in each nozzle 52 communicate with a longitudinallyextending bore 53 in the nozzle and said bore 53 is connected to asuitable suction device 53a, wherefore the nozzles and tubes act towithdraw the moisture from the belt and pa-rticularly from the oraminousbelt shown in Figs. 3, 4 and 5 and the composition deposited thereon. Itwill be understood that when the metal belt 4l is used as thecomposition supporting member the suction devices just described neednot be operated.

A series of air pipes 54 is located beneath the lower reach of theendless belt and said pipes extend transversely of the belt and areprovided with a plurality of longitudinally spaced radially projectingoutlet nozzles 55. The pipes 54 communicate with a manifold conduit 5S,see Fig. 2, and said manifold conduit 56 is in communication with asuitable source of supply of hot, warm or cold air under pressuredepending upon the type of composition which is being formed into sheetsor webs and such air blasts act on the composition on the belt lll orthe belt 48 to condition, dry or set the same as the case may be.

The walls Il just to the left of the roller 38 support a suitableseparating device 5l which separates the conditioned sheet or web fromthe belt, it being noted that a supporting roller 58 is rotatablycarried by the walls i i directly beneath the roller 38 to support thesheet or web as it is separated from the belt.

i If sheets are being produced by the apparatus the separated sheetswill be carried over a suitable horizontal conveyor and through a drierand then stacked. However, in the apparatus shown in the drawing, a webis illustrated as currently being produced by the apparatus and theseparated web W (Fig. l) passes through a drier chamber now to bedescribed and is Wound upon a drum or reel 59 rotatably supported bysuitable standards 6U projecting upwardly from the base l, it beingunderstood that said reel can be driven in any suitable manner wellknown in the art and at the proper take-up speed.

The drier chamber through which the web W passes includes side wallsllc'l extending upwardly from the base IE and merging into upwardlyprojecting standards Si which rotatably support at their upper endsrollers 62. The walls Ha rotatably support adjacent the base of thestandards 6l rollers E3 and the web W is reeved around the rollers 83and 62 so as to provide a plurality of reaches of the web within thehousing B of the drier chamber. The walls l la and the housing B4support air pipes 65 similar to air pipes 54, with the outlet nozzles ofsaid pipes directed to eject blasts of air or other drying medium intothe drying chamber and along both sides of the web at each of thereaches thereof. The housing 64 is provided with a stack 66 thatcommunicates with the interior of the housing 54 through the opening Blto draw away the moisture-laden air from the drier. Also, if desired, anair pipe 65 may be so located that the air blasts from the nozzles willengage the upper side of the web intermediate the drive roller 38 andthe right hand roller 63 as viewed in Fig. 1.

It will be understood that in place or the air pipes 54 and 65 othersuitable drying or conditioning devices might be employed to raise orlower the temperature of the sheets or webs to eiect the conditioning,drying or setting thereof to enable the sheets or webs to be handled. twill also be understood that When said sheets or webs are stripped fromthe belt they will by that time have attained sufcient strength topermit them to be reeved through the drying chamber and wound upon thereel 59 or in the case of sheets to be handled and stacked.

in addition, it will be appreciated that at the start of the operationof producing the web a suicient length of the web will iirst be produceduntil a short length thereof has been stripped from the belt by theseparating element 5l and that such short length can be attached to asuitable lead-in strip which is connected to the reel 59 and is reevedaround the rollers of the drying chamber and thus the newly formed webcan be reeved around the pulleys of the drying chamber and onto the reel59.

The left hand upper corners of the walls Il as viewed in Figs. l and 3have supporting arms 31' upwardly extending therefrom and whichrotatably mount at their upper ends a roll of a suitable reenforcing orreceiving base material or element as, for instance, open mesh screen orcloth 84 and said screen or cloth extends around a guide roller S6carried by the supporting arms 8l and vertically adjustable by adjustingmeans indicated at 88. The adjustment of the roller S5 is for thepurpose of providing desired spacing, if any, between the reenforcing orreceiving material 84 and the endless belt and said material extendsover the upper reach of the endless belt and around the rollers ci? and4I. The reenforcing or receiving material is utilized when it is desiredto have the same integrated or coated with or embedded in thecomposition containing the magnetically responsive or electricallychargeable material that is deposited on the belt to forma sheet or webincluding the base material or element and the deposited composition andthis is clearly indicated in Fig. 5.

It will be understood that the reenforcing or receiving base material orelement can be arranged to lie directly on the belt and to have thecomposition deposited thereon and integrated therewith in the form of acoating or in other instances the reenforcing material can be spacedfrom the belt and the composition deposited so as to embed thereenforcing material therein. The adjustment of the pulley 86 determinesthe spacing of the base material or element from the belt at the rstdeposit station and thereafter the base material is held in properrelationship to the belt by the composition deposited at the firstdeposit station.

It will be understood that in those instances where the base material orelement is employed said material can rst be reeved through the dryingchamber and onto the reel 59 before commencing to deposit thecomposition upon the base material and hence the base material will inthis instance act as the lead for the web.

The on and ofi switch 68 may be located in the lead 69 of the electricalcircuit of the lield windings of the electromagnets 35, the other lead osaid circuit being the lead lil. It will be understood that the leads SQand 'l0 extend to a suitable source of supply of electrical energy andthat the main on and off switch 68 can be manually operated orautomatically operated at predetermined time intervals, and particularlywhen the apparatus is being employed to produce sheets, it beingunderstood that when the electrical circuit is interrupted and the iieldwindings of the elcctromagnets deenergized no composition will bedeposited on the belt and thus the length of the sheets can becontrolled.

I9: In ,order to ionize the .electrically chargeable materials in thecompositions to render the same mobile and thus magnetically responsiveand thus to enect the transfer of the composition from the retainingelement 29 to the belt or to the base material or element under theaction of the electromagnetic field or fields of force it is proposed toimpress on the electrically charge- :able materials of the compositionson the retaining element 29 and to impress on the belt Aand the basematerial an electrostatic charge vwith a resultant electrostatic fieldof force extending to the belt and including the composition on theretaining element. As already stated, the electrical charge impressed onthe electrically chargeable materials vof the compositions on theretaining element 25 causes such :materials to be ionized and theelectrostatic field of force established by the charges on the.composition and the belt initiates migration of the composition andrenders the mobile composition susceptible to the electromagneticforces, with the result that migration of the composition from theretaining element to the receiving member is initiated by theelectrostatic held of force and then finally is effected under theinfluence of the electromagnetic leld or elds of force combined with theinfluence of the electrostatic eld of force.

A terminal 'H is located closely adjacent to the retaining element 29and is connected by a lead l2 to the contact 13 of a reverser switch ll.A terminal 'I5 is located closely adjacent to the upper surface of thebelt in advance of the transfer zone and is connected by a lead l to thecontact 1'! of the reverser switch i4. An adjustable rheostat 'F3 islocated in the lead is. The contacts 13 and 'il of the reverser switchlil are connected, respectively, with the contacts li) and 8 of saidswitch, while the movable switch blade is connected with leads Bl and 82that extend to a source of high potential electrical energy and in whichleads is located a main on and oil .switch 83. It will thus be seen thatthe polarities of the terminals 'H and 'l5 and the voltages impressedthereon can be selected 'by the reverser switch 'M and the adjustablerheostat 'E8 and lsaid polarities and voltages will be selected inlaccord-ance with the particular electrically chargeable material in agiven composition, that is determination Will be made as to the mosteffective polarity and voltage for ionizing the electrically chargeablematerial in order to initiate the' migration thereof and make itresponsive to magnetic induence.

The terminals 'Il and 'l5 impress electrical charges on the electricallychargeable material of the composition on the retaining element 2S andon the belt or base material and these charges ionize `the electricallychargeable material and establish an electrostatic field of force whichinitiates migration of the composition rendering the same responsive tomagnetic forces and thereafter assisting the magnetic lines of force ofthe electromagnetic eld of force to cause the migration of thecomposition from the retaining element 2s and onto the belt or basematerial in the form voi" a deposit.

It will be understood that a similar arrangement is employed for each ofthe transfer and deposit stations and that the terminal l5 at thosestations beyond the rst station will impress an electrical charge on thecomposition previously deposited on the belt -or base material and alsoon the j belt and base material.

It has already been explained that the magnets 35 are connected by leads-59 and lil to a suitable source of electrical energy and that the mainon and off switch 68 is located in the lead Sil, so that the current tothe magnets can be interrupted by manually or automatically operatingsaid switch.

It will be understood also that a suitable adjustable rheostat can bearranged in the circuit to the magnets to vary the current to the fieldwindings thereof and thus to vary the strength of the magnetic field.

Assuming that a nlm-like web is to be produced in the apparatus and thatall three deposit stations of the apparatus are to be utilized toprovide the desired thickness in the web, the reservoir tanks i3 will besupplied with a suitable composition in liquid or semi-liquid form andcontaining magnetically responsive or electrically chargeable andionizable material.

Further assuming that the valve means it. has been opened until thedesired amount of the composition has owed into the auxiliary or supplytanks i3, after which the valve means has been closed and pressure fluidadmitted to the conduits d to create the desired pressure heads in thetanks I8. As already stated, the pressure heads established in the tanksi8 are for the purpose of facilitating the iiow of the composition fromsaid tanks through the nozzles i9 and onto the plates 22 and thus thepressure of such pressure heads will vary in accordance with theparticular type of composition employed. The compositions on the plates22 iiow downwardly of said plates and onto the combs of the retainingelements 28 with the compositions being retained on the combs and in thespace between theplates 22 and the combs by capillary action.

Certain types of composition may require the application of heat tofacilitate the nowing or" the composition and in such cases the heaters23 can be utilized. The operator now causes the motor t2 to function tomove the steel belt all at the desired speed .and adjusts the rheostat'i8 to produce the desired "voltage in the circuit to the terminals 'lland l5. In addition, the operator positions the reverser switch 'ifi toeect the polarities for the terminals li and l5 in accordance with thepolarities best suited for the particular composition. Also the switch58 in the circuit to the electromagnets 35 is closed to energize saidmagnets and create the magnetic iield of force between the field bars 3Eof the magnets. Likewise, the operator causes air to be supplied to thepipes 54 and, as already stated, this air may be cool, warm or hotdepending upon the character of the composition.

The terminals 'il and Ed electrically charge the material in thecomposition and the belt `5l. This charging of the material in thecomposition, if such material is not normally susceptible to magneticinnuence, ionizes the material, initiates migrating movement of thecomposition and renders it susceptible to magnetic iniiuence.Consequently the electromagnetic eld of force created. by the energizedelectromagnets acts on the now mobile and magnetically responsivematerial on the retaining element 2S and effects the transfer oi thecomposition containing such material from said retaining element to thebelt fil. 1n addition, the electrical charges on the material of thecomposition and on the belt produce an electrostatic eld of force whichinitiates and then assists the electromagnetic held of force in themigration of the composition from the retaining element 29 to the belt.

It will be understood that the composition from the retaining element 29at the rst deposit station is deposited directly on the belt, while thecomposition from the retaining element 29 at the succeeding depositstations is deposited on the previously deposited composition.

The thickness of the deposits of the composition on the belt can beregulated in three Ways, i. e., by the air pressures in the tanks i8 tocontrol the volume of flow of the composition; by variations in thecurrent to the terminals li and 'l5 and in the current to theelectromagnets 35 to vary the intensity of the magnetic field oi force,and by variations in the speed of travel of the belt.

As the deposited composition moves with the belt to the lower reachthereof said composition becomes dried or set or conditioned by theaction of the air blasts from the pipes 54. As soon as the separatingdevice 5l has separated a short length or the deposited and conditionedcomposition from the belt this length of the composition is quicklyattached by the operator to a lead-in which extends from the reel 59 andhas been reeved around the rollers in the drying chamber as previouslyexplained. The process then con tinues and the web as it is formed andpreliminarily dried, set or conditioned is separated from the belt bythe separating device 51 and passes through the drier where it isfurther dried, set or conditioned and is then wound upon the reel 59.During the operation of the apparatus the operator will observe the airgauges 2l to make sure that the desired air pressures are maintained inthe tanks I8.

If the clutches in the drive trains 43 are disengaged `the retainingelements 2S will be stationary and the deposits of the composition fromthe comb teeth of the retaining elements will be straight line depositsas indicated in Fig. 7 but such deposits are closely spaced and willmerge together on the belt.

If the clutches in the driven trains i3 are engaged the retainingelements 29 will be oscillated and the deposits on the belt will be ofwavy formation as indicated in Fig. 8 and will then merge together onthe belt.

Assuming it is desired to produce a web of three diierent nlm-likecompositions arranged in three laminated layers, the reservoir tanks 3and the respective supply tanks i8 will be supplied, respectively, .viththe three dilerent compositions so that the composition from the lefthand or rst station is deposited directly on the belt, the compositionfrom the intermediate station is deposited on the iirst deposit ofcomposition While the composition from the third station is deposited inthe second deposit oi composition.

It may be that the three diierent compositions have diierent flowcharacteristics which makes it desirable to have three differentpressure heads created in the tanks i8 and the operator can readilyregulate the pressure in the tanks for the desired purpose. It may alsobe that the three different compositions will each react to transfer anddeposit by electromagnetic fields of force of different intensities .andalso will require electrical charges on the materials in thecompositions of different strength and polarities. In such a situationthe operator can take care of it by means of the individually controlledcircuit at each station for the electromagnets and for the terminals Hand l5.

fili

iii)

It will be understood that a laminated web may be produced in theapparatus in the same way as the web formed of a single composition aspreviously explained but with the differences above pointed out.

The use of the apparatus and the practice of the method has beenexplained above in connection with the making of film-like webs. When itis desired to use the apparatus and practice the method to makefilm-like sheets the switch 68 or both the switch 68 and the switch 83can be opened momentarily at predetermined intervals either manually orautomatically to interrupt the electromagnetic iields of force and theelectrical charges on the material in the composition to momentarilyinterrupt the transfer and deposit of the composition so as to provideintervals between the successive sheets on the belt 4l'. As alreadyexplained the sheets thus formed when separated from the belt will beconveyed through a similar drier by a modied form of conveyor.

Assuming that it is desired to produce a fibrouslike web or sheet from acomposition in liquid or semi-liquid form and containing electricallychargeable and ionizable bers, then the metal belt 41 is removed and theforaminous belt 48 of Figs. 3 and 4 is substituted. The composition isintroduced into the reservoir tanks i3 and supply tanks I8 and thepressure heads for the tanks are regulated to cause the desired ilow ofthe composition while the strength of the magnetic eld of force and thepolarities and strength of the circuit to terminals 'H and 15 areregulated as required.

The electricallyT chargeable fibers of the composition on the retainingelements 29 are charged and ionized by the terminal 'Il and thereuponthe composition becomes mobile and susceptible to the action of themagnetic eld of force and will be transferred under the influence ofsaid eld of force and assisted by theiniluence of the electrostatic eldof force created by the terminals l! and l5 onto the belt 48 and thethickness of the deposits can be regulated by regulating the speed ofthe belt as well as by regulating the pressure heads and the voltages.Inasmuch as the belt 48 is foraminous, being formed of felt interposedbetween the fine mesh, the suction nozzles 52 in the rotatable tubes 49will act to draw the moisture from the deposited composition to dry saidcomposition and to cause the bers thereof to become felted together.This drying action is commenced in the upper reach of the belt and iscarried on through the lower reach thereof, being facilitated in thelatter instance by the air blasts from the pipes 54. Preferably wheniibrous-like webs or sheets are being formed the retaining elements 29Will be oscillated to eiect the wavy line deposits of Fig. 8, since suchwavy deposits of the composition facilitate and strengthen the feltingtogether of the bers as it tends to cause the same to interlock witheach other.

It will be understood that fibrous-like webs or sheets W1 will beproduced similarly to the production of webs or sheets of film asalready explained. It will be understood also that laminated brous-likewebs or sheets can be formed by depositing two or more layers ofsuitable compositions on the belt similarly to the production oflaminated film-like webs or sheets as heretofore described.

It may be desired to produce reenforced :tilmlke 0r fibrous-like Webs orsheets W2. In such case the reenforcing cloth or element 84 is passedfrom the rolls 85 over the upper reach of the belt and around thepulleys 4l) and 4l with the belt and then through the drier to the reel59, the guide roller 8S being suitably adjusted to provide the desiredspace between the reeniorcing element and the belt at the rst depositstation. The apparatus is then operated in the manner already explainedto cause a deposit of a suitable composition to be made on the belt andeither on the element 84 or to embed the element 84.

It will be understood that the deposit of the composition occurring atthe first deposit station then maintains the reenforcing element 8d inthe desired relationship with respect to the belt for the other depositstations. Thus the reenforcing element will be uniformly embedded orpositioned in the webs or sheets produced.

In Fig. the reenforcing element is shown as embedded in a fibrous-likeweb or sheet W2 but it will be readily understood that said element canbe similarly embedded in a felt-like web or sheet.

It will be understood that when reenforced sheets are produced the saidsheets due to the reenforcing element S4 can be conveyed through thedrier as shown in Fig. l and wound upon the reel or drum 59, after whichthe reenforcing element can be severed intermediate the ends of thesheets.

As previously pointed out, the composition may be deposited on thereceiving base material or element in the form of a layer or coating andin such instances the base material or element need not be spaced fromthe support.

It will also be recalled that a sheet or web of one composition may bedeposited or preformed at the iirst station and then a layer or coatingof another or the same composition deposited on the web or sheet at asubsequent station.

It will be understood that when the composition contains magneticresponsive material such as metal particles or powder then it is notessential to electrically charge and ionize the material and in suchinstances the circuit to the terminals ll and 'i5 may remain open andthe composition will be caused to migrate from the retaining element 29to the belt by the action of the electromagnetic eld of force.

The term atmospheric gap as used herein means a gap between theretaining element and the belt or base material which is subject to theatmospheric conditions and pressures of the room in which the apparatusis located and used as distinguished from the space between electrodesor between elements located in a small conned vacuum chamber or thespace between a cathode and anode located in an electrochemical bath.

The term magnetic responsive material or the term magneticallyresponsive material as used in the specication and claims refers tometal particles or powder formed of iron, nickel or cobalt.

It will be understood that the invention is not limited to the specificforms herein referred to but can be varied within the scope of theappended claim.

Having thus described my invention, I claim:

The method or" making webs, sheets or coatings which comprises creatingand maintaining an electromagnetic eld or" force throughout a zoneextending the complete transverse width of the web, sheet or coating tobe produced and including an atmospheric gap between an elongateddepending retaining element and a spaced elongated electromagneticdevice, simultaneously and continuously during the maintenance of theelectromagnetic field of force moving an intercepting member linearlythrough said atmospheric gap at a predetermined rate, simultaneously andcontinuously during the maintenance of the electromagnetic field offorce iowing at a regulated ilow rate liquified composition in flowableform and containing electrically chargeable material onto said retainingelement in the form of a nlm of predetermined thickness such that thenlm of composition normally would be retained cn said element by surfacetension, simultaneously and continuously during the maintenance ci theelectromagnetic eld or" force inducing electrostatic charges on the nlmof composition on the retaining element and on the intercepting memberto ionize the electrical chargeable material and to create anelectrostatic eld of force of such strength as to initiate migration ofthe composition from the retaining element across the atmospheric gaptoward the intercepting member and thus render the compositionresponsive to the electromagnetic'eld of force to effect the completemigration of the composition across the atmospheric gap to theintercepting member in the form of a continuous depositen the member forthe required transverse width of the web, sheet or coating, and thenpassing the moving member and the deposited composition when outside thezone of the two iields of force through air currents to solidify thedeposited composition by the thermal and dehumidifying action of the aircurrents.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 2,224,391 Huebner Dec. 10, 1940 2,318,571 Carlton May 4, 19432,376,343 Carlton c May 22, 1945

